Oil filter



F. R. OGlLVIE Aug. 5, 1952 OIL FILTER Filed April 4, 1949 INVEN TOR. 594M 06/1 10:

Fat-exited Aug. 1952 srares' ATENT orrice OIL FILTER Frank R. OgilVie, Glendora, Calif assignor to Engine Life Products Corporation, El Monte, Califl, a corporation of California.

Application April 4, 1949, Serial No. 85,361

2 Claims. (01. 210-1 83) This invention relates to and in general has for its object the provision of a filter of the character used for the filtration of crankcase oils, and wherein a slurry by-pass valve is ineorporated in a filter unit including a filter cartridge mounted within a sealed casing in closed circuit with the crankcase of an engine.

v More specifically, the object of this invention is the provision, in conjunction with a filter unit of the character above described, of a simply constructed piston type of by-pass valve incorporated' within the filter unit and which serves to by-pass the oil entering the casing to its outlet in response to the existence of a predetermined difierential pressure between the exterior and interior of the filter cell.

The invention possesses other advantageous features, some of which, with the foregoing, will be set forth at length in the following description where that form of the invention which has been selected for illustration in the drawings accompanying and forming a part of the present specification is outlined in full. In said drawings, one form of the invention is shown, but it is to be understood that it is not limited to such form, since the invention as set forth in the claims maybe embodied in a plurality of forms.

The single figure shown in the accompanying drawing is a vertical mid-section of a crankcase oil filter embodying the objects of my invention.

, edge, the ring 5 being provided with an inwardly and upwardly inclined flange 6 forming a downwardly "converging channel I. Welded and sealedto the lower end of the shell 5 is a dished bottomor head 8 and welded to this head coaxially with the shells is a'threaded, downwardly extending filtrate outlet nipple 9. Threaded to-the nipple 9 is an elbow II and threaded to the elbow is a pipe I2 for returning the filtered oil or other liquid to the crankcase of an engine or other receptacle. Welded to the lower end of the shell i and forming a downward continuation thereof is a bracket l3 provided with cut-outs I l, and serving as a means by which the filter unit can be. mounted 2 on an engine or other supporting structure. Welded to the shell adjacent its upper end is a, threaded slurry inlet nipple l5 registering with an opening l6 formed in the shell. Welded.

to and within the shell over the opening it is a coarse screen ll. Threaded to the slurry inlet nipple i5 is a pipe It for connecting the filter unit to a source of oil or other liquid to be filtered. I

Welded to the bottom'or head 8 in vertical alignment with its nipple 9. is an upstandingfiltrate tube l9 formed intermediate its ends with perforations 2i and provided with an upper threaded end 22. adjacent its lower end is an annular supporting plate 23 serving as a support for thecartridge 2.

The cartridge 2 includes a spool 24- provided with outwardly extending end flanges 25 and 26 and formed throughout its area with perfora-' tions 21. Mounted on the spool 24 is an annular j body of filter medium 28 of any desired construction and texture, the lower end of the filter medium being in surface engagement with .the upper face of the supporting plate 23. i 1

Accommodated within the channel 1 of. the

ring 5 is a gasket 29 wedge-shaped in cross section and seated on' this gasket is an upper casing head or cover 30 formed with a central opening 3| and with a spherical seat 32. Welded to and depending from the inner face of the cover 30 is a ring 33 circumscribing the upper end of the filtrate tube I9 and provided with peripherally spaced cut-outs 34'. Sealed to the ring 33 over its cut-outs 34 are fine mesh drainage screens 35. Welded'to the lower flanged .edgeof .the ring 33 is an upper. annular supporting. plate 36, the lower face of this plate being in surface engagement with the upper end of the car-' tridge 2 thereby to prevent the passa'ge'of un-ffiltered oil between these two members.

The by-pass valve 3 includes a sleeve' 38. dis-1 posed-within the upper end of the filtrate. tube- [3 and welded thereto at its upper edge. Slid ably disposed within the sleeve 38'is. a pistontively. One or more of the holes 45 can be threaded for the reception of a screw 46 serving Welded to the filtrate'tube l3,

to limit the upward movement of the piston cylinder 39, the limit of the downward movement of this piston being determined by the upwardly extending flange of the stop member 42. Formed in the piston cylinder 39 adjacent its upper end are a plurality of openings 41 arranged to be brought into registration with peripherally aligned openings 48 formed in the upper end of the tube l9 and sleeve 48 when the piston cylinder is in its lowermost position as determined by the stop member 42.

Threaded over the upper end of the filtrate tube [9 is a nut 49 provided intermediate its ends with a downwardly convex spheroidal shoulder 5| complementary to the spheroidal seat formed in the cover 30. Receivable in the seat 32 is a gasket 52 for sealing the nut 59 to the cover 39 when the nut is screwed home. In addition to or as a substitute for the usual wrench faces provided on a nut, the nut 49 may be provided with a wrench rod 53. For ease in the assembly of. this device a wire ring 54 is clipped to the lower threaded endof the nut 49, this ring serving to loosely interlock the nut to the cap 3U.

During the operation of this unit, unfiltered oil or other slurry entering the unit through the inlet nipple l5 must pass through the unit either by way of the filter medium 28 or by way of the fine mesh drainage screen 35. Normally, the bulk of the oil passes through the filter medium, rather than through the coarser drainage screens 35, for the surface area of the filter medium is far greater than the surface area of the screens. The oil passing through the filter medium and through the perforations of the spool 21 enters the filtrate tube'l9 through its perforations 2| and passes out of the unit through the slurry outlet 9 and the filtrate pipe 12. When, however, the outer surface of the-filter medium becomes plugged or blinded, the slurry will take the path of least resistance through the drainage screens 35,. a portion of such oil passing through the registering openings 44 and 45 formed in the filtrate tube l9 and its associated sleeve 38. That portion of the tube l9 above the piston cylinder 39 .will therefore, .alwaysibe subjected; to sub-1 stantially the pressure of, the slurry disposed within the shellv 4 and,v external to the filter cartridge 2. When the slurry pressure has been built up to a. predetermined selected value, it will move the piston cylinder 39 downwardly against the biasing action ofv the spring 43 and :bring its openings 4] into registration withthe openings 48 formed in the tube l9 and the sleeve 38. Upon such registration of these openings, the slurry strained by passing through the screens 35 will be by-passed directly through the piston valve into :the tube 19 and through the tube l9 out of the filter unit. 9 7

From the above description it will be seen that I have provided a positively acting and simply constructed by-pass valve in conjunction with a filter unit wherebywhen the filter medium of the unit becomes plugged or blinded the incoming oil willbe by-passed to the outlet of the unit.

,I claim:

' 1. n filter comprising: a filter casing including opposed end members and provided with'a slurry inlet and a filtrate outlet; a tube extending across and sealed to said opposed end members with one end thereof in open communication with said filtrate outlet; a cylindrical filter cartridge surrounding said tube and communicating with the interior thereof through holes formed in said tube Within the length of said cartridge; a filter screen surrounding said tube and extending from the end member opposite the filtrate outlet to the filter cartridge; a spring biased piston valve disposed within said tube where said tube is surrounded by said filter screen, the inner end of said piston valve being in open communication with said filtrate outlet through said tube and its outer end being closed, said tube and said piston valve being provided with normally nonregistering ports and said tube being formed with a port outward of the outer end of said piston valve and which serves to subject the outer end of said piston to slurry pressure within said casing and external to said cartridge. V

2. A device of the character described comprising a casing having a slurry inlet formed therein, abase member secured to and sealing the bottom of said casing, said base member having, a filtrate outlet formed therein, a tube connected to said filtrate outlet and extending longitudinally with said casing, threadably receivable on the upper end of said .tube and sealing the upper end of said casing,

a primary filter cartridge surrounding said tube and communicating with the interior thereof through holes formed in said tube within the length of said cartridge, a secondary filter screen surrounding said tube and extending between said primary filter cartridge and said top member, whereby when said primary filter becomes plugged said slurry passes through said secondary filter screen and into communication with said tube above said filter cartridge, a springbiased piston valve disposed within said tube Where said tube is surrounded by said secondary filter screen, the face of said piston being in open communication to the external pressure on said tube, the

r interior of said piston being in open communication with the interior of said tube, said tubeand the side wall of, said piston valve havingnormally non-registering ports, whereby the external pressure on said piston causes said piston to so move as to align said normally non-registering ports, whereby the filtrate which has passed through said secondary filter screen fiows into and through said tube and out through said filtrate outlet. 7 FRANK R. OGILVIE'.

REFERENCES CITED The following references are of record the file of this patent:

Kovacs et al. Dec. 121950 a top member 

